Machine for treating hides, skins, and leather



Sept. 14, 1948. 2,449,128

c. D. KNOWLTON ET AL MACHINE FOR TREATING HIDES, SKINS, AND.LEATHER Filed July 25, 1947" [nven tors Gufler' D. Know/tan Dal/id Edgar, B U2 [7' nay Sept. 14, 1948. U c. D. KNOWLTON ETAL 2,449,128

MACHINE FOR TREATING HIDES, SKINS, AN LEATHER Filed July 25, 1947 Sheets- -Sheet 2 [nven to rs Cutler-D. Knowlzfon Patented Sept. 14, 1948 UNITE I STATEfi MACHINE FOR TREATING HIDES, SKINS, AND LEATHER Cutler D. Knowlton, Rockport, and David Edgar,

Lynn, Mass, assignors to United; Shoe Machinery Corporation, Flcmington, N. J a corporation of New Jersey Application July 23, 1947, Serial No. 762,916

13 Claims.

This invention relates to a machine for treating hides, skins, and leather, and more particularly to improvements in the operating rolls of staking machines of the type disclosed in United States Letters Patent No. 2,359,922, filed August 24, 1942, upon an application of Cutler D. Knowlton and David Edgar, original Patent No. 2,359,922 being reissued June 5, 1945, Reissue No. 22,649. While the invention is herein illustrated as embodied in a leather working machine, it is to be understood that in various novel aspects it is not thus limited in use but is more generally applicable to machines for performing operations other than staking operations.

In subjecting a hide or skin to the softening and stretching treatment of meshed helically bladed rolls in a staking machine of the above mentioned type, it is essential that all portions of the work piece be rather uniformly acted upon. However, it has been found that in using staking machine rolls in which spiral blades extend with constant lead but in opposite directions from a substantially central point in their length, the work piece fed into the rolls, whether it be of varying or of uniform thickness, does not properly spread out as its adjoining portions are being worked upon by the bending and pressing action of the blades. A common result is that a work piece may in some portions be rigorously treated while remaining portions undergo relatively slight staking action. Moreover, When a work piece is fed between constant lead staking roll blades somewhat to one side of the center of the machine of the type above referred to, it is found that the work piece will be caused to veer further to that side and so partially escape the uniform stretching action desired longitudinally of the blades.

It is an object of this invention to provide a machine having improved operating rolls cooperating to assure uniform and complete staking treatment of all portions of a work piece. A further object of the invention is to provide a staking machine to which an operator may initia'te feeding of a given work piece without the necessity for carefully or accurately introducing it centrally of the working rolls.

To the attainment of these objects, an important feature of the invention resides in the provision of cooperating rotary work treating members for attaining a spreading out of the work piece when fed between the members, said members comprising rolls carrying interacting helical blades which extend in opposite directions from a substantially median point in their length.

and have a greater lead nearer said point than toward the outer ends of the rolls.

A further feature of the invention is the combination in a staking machine of interacting helically bladed rolls in which the lead is not uniform, the pressure applying surfaces of said blades forming involute teeth, and the blades of one of said rolls being of substantial rigidity and rather sharply edged while the blades of the other are covered by yieldablematerial and have well rounded outer edges.

Another feature of the invention is the provi-' sion of means by which a Work roll is yieldingly driven to effect a more quiet and non-scuffing treatment of the work piece, operating power bein transmitted to the shaft of the roll through blade flexibly associated with the driving mechanism.

A still further feature of the invention-reside in the provision of convenient means for maintaining uniform meshing and clearance between the interacting bladed rolls.

The'above and other features of the invention, including various novel details of construction and combinations of parts will now be more particularly described with reference to the accompanying drawings and thereafter pointed out inthe claims.

In the drawings,

Fig. 1 is a view partly in front elevation and partly in section of a portion of a machine of the type disclosed in the above mentioned Patent Reissue 22,649 and in which the present invention is embodied, showing cooperating bladedrolls which operate upon the work;

Fig. 2 is a somewhat diagrammatic cross-section through the bladed rolls taken along the line IIII of Fig. 1, and showing a work piece being fed upon a conveyor belt;

Fig. 3 is an enlarged end elevation showing the leaf spring or spring blade mounting through which the upper roll is yieldingly driven; and

Fig. 4 is a section taken on the line IV-IV of Fig. 3, with thespring blade shown in full and indicating the driven end of the upper shaft and.

its association with the spring blade and driving sprocket.

In view of the disclosure in the above mentioned Letters Patent of the general organization of machines of the type herein illustrated, only such parts of the machine as it is necessary to refer to for an understanding of the invention will be' herein described in detail. For convenience Figs. 1 and 2 of the drawings furnished herewith are similar to Figs. 15 and 1 8 of that patent.

' lower work-treating roll An upper and a lower horizontal work-treating member or roll, bearing the general designations II) and I2 respectively, have oppositely driven shafts I4, I6 respectively mounted in bearings as set forth in the above cited Letters Patent and as will now be briefly described. Referring to Fig. l, shaft I4 is supported in bearings I8 carried by brackets (not shown) mounted on a machine frame 26 to receive each end of the shaft I4. The I2 is substantially parallel with roll I and has its shaft I6 mounted at each end in bearings 22 supported by frame 26 and carried at the upper ends of a pair of arms 24, each pivoted on a rod (not shown) in an arrangement in which each arm 24 is fastened to a tubular member 26 having secured to its 'middle portion a downwardly extending lever 28. Through manipulation of control members connecting with the lever 28, which control members are not herein shown since they are substantially the same as those fully shown and described in the previously mentioned Letters Patent, an operator is enabled to move arms 24 upwardly or downwardly to adjust the lower roll I2 with respect to the'upper roll Iii. As disclosed in the previously mentioned Letters Patent, machines of the type herein disclosed are provided with work-feeding means including a conveyor belt 66 arranged to feed a work piece toward and away from the bite of rolls I6 and I2.

As used herein in connection with the spiral blades of rolls I6 and I2, the word lead" is intended to mean the distance of translation of the blade as it advances along the axis in one turn around the roll.

Extending in opposite directions from a median point or line in the length of upper roll I6, shaft I4 carries substantially rigid helical blades'or pressure applying ribs in a plurality of sections 34, 36,

3'8, 40 and 42, 44, 46, 48 arranged to mesh with cora:

responding helical blades in a plurality of sections 35, 31, 39, 4|, and 43, 45, 41, 49 of presser roll I2 which are covered with a yieldable material, such as felt. As shown in Fig. 2, the interacting blades of both rolls are involute in cross-section, the blades of upper roll I0 having rather acute staking edges while thoseof lower roll I2 are well rounded for protection of their felt coverings. Preferably, all the blades are of substantial rigidit y so as to prevent their bending in operation, and in this connection it is deemed desirable to aid in sustaining their contour by having them symmetrical in cross-section though it will be understood that that blade surface which does not engage the workpiece need not necessarily be symmetric in cross-section with the working surface of theblade nor be involute in contour. 'It is also preferable, as illustrated, to have four annular blades in each roll cross-section. Staking rolls having greater diameters may well have a larger number of blades. The more nearly central sections 34, .42 and 35, 43 have blades of equal and opposed lead, and are held in fixed relative rotative positions by keys 56 and 58 inserted in keyways of their respective shafts I4 and I6. Also it is to be noted the blades nearer the median point of their respective rolls have the greater lead. The

lead of the more outwardly continuing blades in,

sections 35 and 44 is accordingly less than that of the blades in the central sections but equal to the lead of the blades in their respective meshing sections 31 and 45. The remaining outer sections 38, 46, 46 and 48 have continuing blades with a lead less than that of the blades in the more inward sections, but equal to that of the blades in their respective meshing sections 39, M, 41 and 49. Within a given section, the lead of the blades therein is constant in order to facilitate construction. The four intermediate sections of each roll are preferably of equal length and the four outer sections of each roll are also preferably of equal length as shown, but the outer sections are each preferably twice the length of an intermediate section. Although these relative dimensions are selected and the lead of the blades in the sections shown decreases in the proportion 3:1 :1 :1 proceeding outwardly from median points in their length, it will be understood many variations are possible and perhaps desirable for other particular work applications.

The sections of the upper roll I0 are not adjustable in position relative to each other, but are firmly fixed in their relative rotative positions by small locking disks 56 inserted between their contiguous section faces. The adjoining sections of blading on lower roll I2 are not locked in their relative rotative positions by inserts or keys. Shafts I4, l6 are threaded to receive nuts 36', 32 respectively which may be turned thereon to press inwardly against retaining rings 52, 52 and 54, 54 respectively, bearing on outside roll sections 46, 48 and M, 46 respectively. Roll I2 as a whole has its resistance to torsional stresses increased by the very high compressive force exerted by the tight ening of nuts 32, 32, a force which may be such as appreciably to stretch shaft I6 to hold firmly all the felt covered sections thereon in their relative positions. The felt covering 55 need not be transversely out between roll sections although it may be so cut.

The mechanism by which shaft I4 of upper work roll I6 is yieldingly driven will be apparent from the following description, having reference to Figs. 3 and 4. A hub 62 is secured to one end of shaft I 4 by a key 63 and a set screw 65. A power-driven sprocket 64 is free to revolve on the hub 62, and both hub 62 and sprocket 64 are retained in posi-' tion by a collar 66 which is aflixed to shaft I4 by a set screw 68. A drum I6 is fitted over the reduced end portion 6| of the hub 62 and is secured to the sprocket 64 by bolts I2. The drum I6 is provided with slots 'II loosely to receive the ends of a spring blade I4 which passes through a central slot in the end portion 6| of the hub 62 and is rigidly held therein at a zone in alinement with the axis of roll I!) by a bolt 16. A hole 18 is bored in the hub 62 merely for convenience in machining the keyway for key 63.

Incorporation of the improved work treating rolls in a staking machine of the type above referred to, does not alter the general operation of themachine as described in the above-mentioned- Knowlton et al. patent. The worker introduces the work piece centrally to the treatment zone be tween rolls I6, I2 while the latter are revolved in the direction of the arrows (Fig. 2) and at a pcripheral speed considerably greater than the rate of feed of the work. In this connection it will be understood that means are employed to' retard the work piece as it is fed; preferably, a work clamping device such as is disclosed in the cited Knowlton et al. patent is operative to hold the work piece against displacement with respect to a conveyor belt. As also indicated by arrows (Fig. 2), while the rolls I I], I2 are always rotated in the directions shown, conveyor means 66 may be arranged to reverse the direction of feed of a work piece. By reason of the greater lead of the more central meshing blades, the work is laterally spread out to eliminate crimping as it is bent and pressed between the interacting work contacting surfaces of the spiral blades. As may be visualized from Fig. 2, the pairs of blades treat both sides of the work piece and stretch it in a direction transversely of the rolls; simultaneously the blade urfaces assert a spreading tension on successive and progressive work piece segments longitudinally of the rolls. The outer sections of the rolls, having the lesser lead, serve to exert a strong outward force upon the work piece being treated and place that work piece under tension longitudinally of the rolls to enhance the staking efiect. The in termediate sections, having a, greater leadi'to their blades, exert less outwardpull on the work piece. Accordingly, the portions. of a work piece disposed at opposite sides of a median point in the length of the rolls will be spread outwardly in opposite directions by longitudinal forces which also assist the operator in maintaining the work piece sen-- trally of the machine.

Although drum is constantly driven in one direction by sprocket 64, the flexible spring blade 1-4 rotates with drum 10 yieldingly to drive shaft l4 and roll I0. Accordingly, instead of being driven into wedging engagements with the work piece in such a way that each engagement may comprise a series of rocking or rebounding surface bites, the uncovered blades of roll I0 are permitted yieldingly to maintain contact pressure on successive segments of the work piece. The slight yielding rotative movement of spring blade 14 in efiect automatically imparts a resilience to the staking action of the blades which prevents scuffing of the work piece surface, and moreover, makes for quiet and more uniform operation of the machine.

Since more staking treatment is likely to occur intermediate the lengths of the two rolls, greatest wear will occur there and excessive clearance therebetween may normally be expected to result from the more rapid wearing of the yieldable covering material on the blades of the presser roll l2. To adjust for such wear and attain correct clearance between interacting blades, nuts 32 may be turned to relieve somewhat their compression of the blade sections of roll l2 and the tension in shaft I6. Rotating the fixed sections of roll It] will cause the working surfaces of its blades to interact accurately with the corresponding worn blade surfaces of roll 12, the relative rotative positions of sections of roll l2 assuming new and proper positions of alinement.

Nuts 32 may then again be turned to tension shaft l6 and to compress and hold the sections of presser roll l2 in a direction parallel with upper roll H! and in their adjusted positions for further staking operations.

Having described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

1. In a machine for operating on hides, skins and leather, a pair of cooperating rotary work treating members each having helical blades extending in opposite directions from a substantially median point in length, the blades nearer said median point having the greater lead, and a side of each blade on one member arranged to interact with a side of one blade on the other member to treat a work piece interposed between them.

2. A machine as set forth in claim 1 further characterized in that means are provided for yieldingly driving one of said work treating members.

3,. In a staking machine for treating hides; skins and leather having a pair of driven rotary work membersbetweenwhich a work piece may be introduced for treatment, substantially rigid blades in contiguous sections arranged helically to extend with opposite and decreasinglead on one of said members froma medianpoint in its length, and blades covered with yieldable material on the other of said members, said last men tioned blades being arranged to cooperate with said rigid blades. I l 4. In a machine'for'operating on hides, skins and leather having work feeding means, a pair of driven rotary work treating members, helical blades extending in opposite directions frorna substantially median'point inthe lengths-of said members, the blades nearer said median point having the greater lead, and the working surfaces ofblades on one member being substantial1y:rigid and arranged to cooperate with the working surfaces of the blades on the other member, said latter working surfaces being yieldable.

5. In a machine for operating on hides, skins and leather, the combination with a conveyor mechanism arranged to feed a work piece to the bite of a pair of cooperating work rolls first in one direction and then in the other direction, of blades arranged helically to extend with decreased lead along one of said rolls in opposite directions from a median point in the length of said roll, and blades covered with yieldable material arranged helically on the other roll to interact with the first mentioned blades, all of said blades being symmetrical in cross-section.

6. In a machine for operating on hides, skins and leather, a pair of cooperating work treating members oppositely driven, each member having helical blades extending in opposite directions from a substantially median point in its length, the blades near said median point having the greater lead, a side of each blade on one member being arranged to interact with a side of one blade on the other member, and means for yieldingly maintaining contact pressure of the blades of one of said members on a work piece between said sides.

7. In a machine for operating on hides, skins and leather wherein oppositely driven cooperating rolls treat both sides of a work piece passed therebetween first in one direction and then in the opposite direction, substantially rigid blades arranged helically on one of said rolls, blades covered with a yieldable material arranged helically on the other of said rolls, all of said blades having interacting surfaces involute in cross section and advancing with increased but opposite lead from the outer ends of said rolls to a median point in their lengths.

8. In a machine for operating on hides, skins and leather, the combination with means for feeding a work piece to the bite of a pair of cooperating work rolls, of substantially rigid blades arranged helically to extend with decreased lead along one of said rolls in opposite directions from a median point in the length of said roll, blades covered with yieldable material arranged helical- 1y on the other roll to interact with the first mentioned blades, and means'associated with said rigid blades for yieldingly maintaining their contact pressure on said work piece.

9. In a machine for operating on hides, skins and leather, a work treating roll, a work engaging roll cooperating with said work treating roll, and means for driving said work treating roll,

said means including a power driven member than toward its ends and one of said rolls being in sections covered with yieldable material, and means for compressing said sections in a direction parallel With the shaft of the latter roll whereby said sections may be held in rotative position with respect to each other.

11. In a machine for operating on hides, skins and leather, wherein oppositely driven cooperating rolls treat both sides of a work piece fed therebetween first in one direction and then in the opposite direction, a frame, a pair of shafts journaled in said frame for supporting said rolls, each of said rolls being comprised of transverse sections disposed laterally of a substantially median point in its length and having interacting helical blades extending in opposite directions from said point, the blades nearer said median point having the greater lead, keys for locking the said sections nearest said point centrally of their respective shafts, locking discs inserted between contiguous faces of the'sections of one roll for holding its blades in fixed rotative position relatively to each other, yieldable material arranged to cover the blades of sections of the'other roll, means for compressing the latter sections in a direction parallel with the shaft of the latter roll, and all of said blades being involute and symmetrical in cross-section. V

12. A machine according to claim 11 in which means is provided for yieldingly driving one of. said cooperating rolls.

13. A machine as set forth in claim 12 further characterized in that said means for yieldingly driving one of said cooperating rolls comprises a hub fixedly associated with said roll, a power driven member revolvable on said hub, afdruzn attached to said member, and a leaf spring mounted in said drum and attached to said hub.

CUTLER D, KNOWLTON. I DAVID EDGAR. r 

